how to close or exit of one of two opened windows?

[Mindy Wu]

Hello all,
I created a swing application e.g A, when use clicks a button in A, it will display B ( another swing interface). My question is how to close B when user clicks Close Button in B without close A.
I know you can set
"frame.setDefaultCloseOperation JFrame.DISPOSE_ON_CLOSE);" to close the frame when user clicks x. If i use System.exit(0), it will cause all of the opening swing screen exit.
Wating for you help!
Thanks!
Mindy

[Cindy Glass]

frame.dispose();